Know how to handle your Neoprene

10 Wetsuit care do’s & don’ts

1.      Rinse well with fresh water after every use

2.      Dry inside out first & then dry the right way out AWAY from direct sunlight

3.      Store right way out and minimise hanger use, or use a padded wetsuit hanger

4.      Keep it flat or folded behind the knees & then in half. Get a dry bag to minimise crumpling

5.      Avoid contacting the Velcro with the inside lining of the wetsuit as this will pull on the sensitive fibres. Keep it covered with the fabric patch

6.      Ensure you do not damage the wetsuit material with fingernails.

7.      Don’t store in the boot of your car! Heat is not neoprene’s friend & cooking wetsuits if only for when you’re reeeaaaally hungry.

8.      Avoid use in Chlorinated swimming pools

9.      Don’t put in the washing machine or tumble dryer.

10.   Don’t wash with detergent or bleach AND DO NOT IRON!!!! (obviously)

FINGERNAILS ARE A WETSUIT’S FOE! Combat them with Black Witch neoprene glue, especially formulated to fix small slices, nicks & loose stitching.

Drowning in wetsuits- a beginners buying guide

When I first thought of wetsuits for open water swimming, my mind automatically went to the thicker sailing/surfing wetsuit designed to keep you warm. You can pick one of these up anywhere these days and for peanuts, but you might as well just bubble wrap yourself because trying to swim fast in one of these is hard to say the least. When you are surfing or similar you want durability and insulation, but for athletic swimming you want a wetsuit that improves your body position in the water.

But I found there were a million and 1 options when it comes to triathlon wetsuits and soon felt like I was drowning in a sea of open internet tabs all showing what appear to be the same- but still totally different wetsuit! Cue a notepad, pen and Starbucks for me as I dived into research, but for you guys – don’t panic. Here’s a simple guide to help familiarise yourself with main brand wetsuits, terms to look out for and debunk odd abbreviations: SCS, Yama 38/39, 3-5mm, ABC, 123, WTF……….

There are 3 ‘F’ factors that determine the quality of a triathlon wetsuit and they are not expletives:

  • FLEXIBITY The efficient movement & flexibility at the shoulders, for your swim stroke
  • FIT The variety of panelling thickness to provide the right coverage at the right places
  • FLOATATION Buoyancy qualities that keep your body positioned right in the water




Panel thickness – Wetsuits are comprised of neoprene panels of varying thicknesses up to 5mm. In areas seeking greater buoyancy, like the legs, 5mm is often used. Thinner neoprene (commonly 3mm) is used where flexibility is needed and buoyancy is less of an issue, like the shoulders and back. In other words, the THINNER the neoprene, the MORE flexible, but less buoyant the panel.

SCS – All should have SCS coating (Super Composite Skin) which is a silicone coating to reduce drag. Some beginners’ suits have nano SCS coating, (just a more slippery coating).

Stitching – Most are glued together and stitched across the seam, some use extra tape at stress points, but top end suits are virtually seamless. But don’t confuse a lack off panelling to a lack of seams – you want the wetsuit to be made of multiple panels to allow for a snug fit, therefore increased flexibility, and a variety of buoyancy (more on that to come).

Material – wetsuits are made from neoprene and as the price rises, you can expect better materials (so go for Yamamoto 39 neoprene instead of 38) for lower drag and improved flexibility, increased durability and an array of marginal-gain innovations like catch panels.




This is the wetsuits buoyancy and what gives you a flat streamlined body position in the water, and what makes swimming with a suit faster than without. However, it’s possible to have too much of a good thing. If you have heavy legs and a poor leg kick, then a suit with a lot of lift in the thighs will help you maintain a neutral body position more easily. But if you already have a good body position and strong kick, too much leg lift can put pressure on your lower back and make your kick less effective. It’s worth looking at the panel construction of your intended suit and thinking about whether you need more/less buoyancy. Panels with a depth of 5mm and/or air cell neoprene in the torso and legs offer the most lift, with some suits going as low as 3mm or 4mm if they’re designed to be more neutral.



When referring to the sizing chart you will probably fit more than one category or size, and this is the trade-off between comfort and performance. If you are new to wetsuits, you will probably opt for the less restricting option and get a size up, whereas if you are used to them, you can go for the smaller size – just think of the sucking in qualities! The theory is that the wetsuit is tight as possible to act as a second skin with minimal drag occurring between you and the wetsuit material. Too loose and water will gush in and out and never warm up; too tight and your stroke will be restricted, leading to fatigue and frustration. So, here are a few things to consider when choosing what size will be best.

A person’s weight is more critical than their height, so if you fall on the margin of sizes, always go with the one closest to your weight. Then you must decide on if you want comfort or performance fit.

Entrance level wetsuits cut slightly straighter around the torso to give a higher level of comfort, while the next step up in wetsuits have a slightly sleeker cut designed to be compressive around the legs and torso, but still maintaining total freedom of movements around the shoulders and arms.

The most important thing when determining whether the size is right for you is first making sure you have put the suit on correctly. The correct fitting wetsuit won’t feel like it fits if it’s not being worn in the correct position. You don’t need contort yourself into advanced level yoga positions to check this, just that you should be able to go through the motion of swimming relatively easily on land, and remember that once wet, the suit will fit better and mould to your shape the more you wear it. Watch this space for an upcoming video!


The benefit of coming to Open Water Swimming with us at Merchant Taylors is that you can try on different sizes and brands before taking the plunge to buy one AND we sell our ex hire wetsuits off at the end of the season for a very discounted price!


…………….But time to stop wittering on, let’s see some actual entry level examples!




Orca – Open Water Core (£129) The cheapest entry level wetsuit, but as you’d expect, the least variety in neoprene, only 2-2.5mm thickness across the body & in sizes XS – XL


Zone 3 – Advanced (£169) Voted the best entry level wetsuit by 220 Triathlon & our preferred brand, with 2mm neoprene on the shoulders & underarms, 3mm on the upper back, & 4mm on the torso, legs & sides.

Huub – Axiom 3:3 women’s & 3:5 men’s (£200) which comes in 2XXS to XL & features a low neckline for comfort. However less variety of thickness across the suit- 3:3 / 3:5 is the mm ratio of upper to lower body. They quote “women have less dense and ‘unique’ body muscular structure making the female more naturally buoyant”. In other words we carry more fat on our thighs than men – jeez thanks for the reminder!

2XU – P:1 Propel £215. As the highest priced wetsuit, it also has the highest variety in thickness across the suit; 5mm upper front chest, 3mm lower front chest, 3mm upper back, 5mm lower back and 1.5mm arms. It is also the only brand offering the XXXL size


5 reasons why Open Water swimming is an absolute must!

When you think of what to do after work or how to start your weekends, you probably don’t automatically go to donning a wetsuit and jumping into a lake. You’re tired, achy and possibly quite stressed, wanting nothing more than to curl up under the duvet and sleep for a week. But it is precisely these times that your mind and body can really benefit from open water swimming and these are just a few reasons why.

1. De-stress
You can’t constantly dose yourself with G&Ts, soak in a bubble bath or zen yourself out with meditation and yoga every day of the week, and if you’ve got kids you’re probably already stretched for “me time”. Exercise is proven to help with stress relief, but the idea of a busy, loud, sweaty gym does not bring relaxation to mind. Wouldn’t it be nice to wash away the stress to leave you feeling revitalised without turning into a very drunk, unproductive wrinkled prune? But you can! All you need is an hour to do a lap at the lake. No rush, no competition, no judgement, and no repercussions!

The science behind this is cold water stimulates the parasympathetic system, which helps your body rest and repair itself. This is opposed to the sympathetic system known as the fight or flight response. Engaging the parasympathetic system releases dopamine and serotonin, and in non-scientific terms, makes you feel happy. Your body’s weightlessness in the water also helps relax your muscles when you’ve been hunched over a desk all day, plus stress usually materialised somewhere on your body (anyone else left with just one raised eyebrow looking slightly demented?)


2. Fitness
I have a gym card and a Starbucks card – and only one of those gets used once a week (I keep the Borehamwood store open- you’re welcome). We all know we should move more and be active after a day at the office, but I am never one of those people that look forward to going to the gym! Swimming is, without question, an effective way to burn calories AND gentle on problem areas like knees or lower back, so a great option even if you’re plagued with injury. Swimming in cold water is much better for burning calories than an indoor pool as your body works every single muscle and is trying to stay warm, so you are increasing muscle tone and endurance at the same time. Plus, releasing dopamine and serotonin promotes a good night sleep (screaming child dependent).


3. Pain relief

I’ve already touched on it with muscle relaxation, but there is nothing worse than trying to do exercise and your body throwing a tantrum right back at you. Trying to run or cycle? Don’t be silly- that’s a 100% NOPE from the knees, and the ankles aren’t on board either. But don’t be disheartened – high impact exercise can be jarring to joints, so don’t stop exercising, just change it. “Water therapy”…also known as swimming to us common folk, unweights joints and helps realign the body without any back cracking or weekly trips to a physio. So just floating like a lazy seal counts as looking after yourself! Many talk about the ‘high’ they get from cold water swimming, caused by the endorphin rush from the sudden change in temperature. Released by your body to take the sting of the cold away from your skin, they are natural pain killers – though do think twice when you get a headache walking along the Thames before you take the plunge in full work attire, we do not sanction this.

4. Circulation

Being hot brings blood to surface. Being cold sends it to your organs. Both extremes work your heart like a pump. SCIENCE. But here’s the beauty benefit of it: by flushing your circulation, it will exfoliate your skin and remove impurities from it, thus helping your complexion and reducing cellulite. It also boosts your hormone levels, and though you could do this in the shower by switching between the hot and cold taps, it’s not nearly as fun! I’ll leave you to do the science…..

5. Having fun with friends!
You’ll find a lot of likeminded people at open water swimming, were all as mad as each other! It doesn’t matter if you’re a seasoned pro or just want to dip your toe in – everyone is welcome, and you do as much or as little as you want to! Nobody will judge your speed, age, outfit choice, size, or hair after all – this is not high school. And once you’re done, grab a coffee or drink at the bar and catch up on how “adulting” is going.
Why Open water over pool swimming?

And if you read this and thought, great, well I’ll just head down to my local pool, why is swimming in a freshwater lake better than a chlorinated pool. This is easy to answer and requires no scientific explanation. Would you rather bright lights, pool lanes & walls, lane hoggers, pushy swimmers, chemicals and splashing kids….or would you like to swim at your own pace, in a natural environment in your own little world? Hint: it’s the second one – time for yourself is often overlooked, but probably one of the most important factors to a happy life.

Expert is for Everyone

As coaches, our goal is to support our athletes to become the best they can be. Personal success is different for all and must take into account the reality of the Age Grouper’s life, which includes demands from work, family and their community.

Unless one is a professional athlete, life does not revolve 100% around training for a sport; rather sport is a part of daily life.  Even with the clearest understanding of how important exercise is to our mental, emotional and physical health it can be a struggle to fit it in with the rest of life’s demands.

The secrets to achieving long term improvements in health and performance are consistency and commitment. Developing positive personal success habits and having patience and persistence is a key part of your long-term development.

Athletes who work with their coach to develop a realistic training program that they can commit to, report high levels of success.

Below are some tips to help maintain consistency and commitment to training:

·        Schedule each workout in an appointment book, Outlook, iCal, Google calendar or whatever you use to plan your week, and make that daily training as important as any other appointment you have that day. Be consistent about showing up and commit your best efforts to that time.

·        Plan in advance what you need before each workout, not when you are ready start. Lay your gear out the night before, wake up early and complete your workout before the family begins to stir. Commit to having good habits and consistently follow them.

·        Let your coach know how much time you have during the workday. A 40-50 minute structured run at lunch is a fantastic work break and an opportunity to add frequency without a lot of volume.  Train during lunch and eat at your desk afterwards. Commit to being proactive about planning your time.

·        For those having children with regular practices, many facilities have programs running concurrently for parents. While the kids are in the pool, join a spin class or yoga session. Apart from being great planning, you are being a great role model for physical activity. Consistently be active while your kids are active and commit to your personal health.

·        When preparing to travel, scout out the location’s resources and plan what, when and where you will make workouts happen before you leave home. Running through a new location is a great way to get a real sense of the community and on top of that, it can be fun.

Remember that commitment to consistent training is the key to improvement and finding balance and incorporating sport into your daily life is the smart way to ensure it happens each day.

Have fun and enjoy your success!

11 Athletes you’ll likely see if you watch an Ironman (and I highly recommend that you do…)

1. The one who is pouring anything they can find on themselves to try to wash away the urine that was recently released all over their shorts and legs.

2. The athlete who motions for the crowd to cheer as they approach on their bike. I LOVE this type of athlete. Their energy and enthusiasm epitomise the spirit of the Ironman. If you don’t cheer for them, you should be banned from spectating.

3. Took as many sponges as humanly possible athlete. This athlete looks like an exotic dancer stuffing £5 notes anywhere they will possibly fit.

4. Biker who throws their water bottle at the fans. At first you may be alarmed, thinking you may of done something to offend this person. But then you realise they are just following the rules by chucking the empties in a race-specific area for easier clean-up.

5. Athlete running the Ironman with one f*%$£ng leg. There is nothing, and I mean nothing, that turns me into a crazy fan than seeing these so-called handicapped people doing things that 99% of “able-bodied” people will never do. I cheer so hard I can actually taste blood (can you rip a vocal cord? Is that possible?)

6. Athlete who has turned themselves into a human billboard for something comically unrelated to running, biking, or swimming.Hey, If you run the race, you should wear whatever you feel like wearing! Just make sure there are big printed words so I can cheer you on (SARAH’S CLEANING SERVICE LOOKING GOOD!” If you print it, the fans will scream it.)

7. Athlete who printed their name AS LARGE AS POSSIBLE on their race kit. In doing so, they have announced to the spectators that they enjoy being cheered for, and therefore people will probably pretend to know you…. “LUCY oh my God is that really you???!! I have been waiting for you for MY WHOLE LIFE!!”

8. The pro who’s curled up vomiting somewhere along the course, but won’t take help because they don’t want to be disqualified.

There are rules about assisting the participants – if you help people it can actually DQ them. I’ve been lucky enough to witness athletes crawling to the finish line, its inspiring to watch people give so much.

9. Guy who bought a nice new white spandex all in one race skin suit and shaved everything. Except his a$$ crack. Which you could see clearly through his white shorts.

10. The one who looks like they just got flour-bombed with sunscreen.

11. Super triumphant athlete. They’re joy is infectious, especially as they cross the holy grail off the finish line.


You have nothing to lose at this time of the season!

Best wishes for your races!

Open Water Swimming Cancelled Wednesday 8th May

Sorry Swimmers but there is just too much lightning this evening and more predicted coming in from the South West.


We run rain or shine and always want to be able to get you guys out in the water….unless there is lightning. Because the best place to be then is definitely not in water, surrounded by trees. Nope nope nope!


Sorry for the last minute decision but we really didn’t want to cancel. Fate now says that as soon as I post this the weather will be beautiful…so hope Hercules has tricked the lightning gods into giving you a pleasant evening!


Hope to see you all this weekend!

1st SWIMRUN? Everything you need to know

SwimRun races. What could be simpler? You swim then run, then swim, then run, then swim, then… well you get the picture. 


What started as an off centre idea in Scandinavia, racing across an archipelago, has now started taking off over here.

The Otillo is the gold standard in Sweden, with qualifying races to be on the start line. Some races over here are either qualifiers or point earning “merit” races.

However, though it seems complex, don’t worry; there are plenty of less hard core athletes entering these races. So let’s help you get race ready, but from your side of the bargain, you will need to do some work.


Pair with someone compatible

First up, you need to find a partner who fits even better than your wetsuit. Choosing a compatible partner is possibly more important than a wetsuit that fits in fact!

You race as a pair and have to stay together all the way – and by stay together we mean, usually within 10 metres of each other. So for context, think of an iron distance race, with a partner, all the way. A horrible idea for some, but once you get used to it, it’s a really great way of working as a team towards race day.

So in choosing a compatible race partner, you will need to be similar in pace. An unequal fitness partnership will never work. You will spend a lot of time together before the race, but also on race day making your way across challenging terrain which will not be familiar to either of you. This means that you will need to have compatible personalities too, as your acquaintance will be thoroughly put to the test.

Even if you are the best of buddies, you will also need to agree that you will hate each other at some point in the race, agree you will probably say you are never doing it again with each other, and it was a stupid idea in the first place. Then once you cross the line, you will be full of how you can do the next one better and how soon can you can get your entry forms in. Trust us, we know these things.


The Right Clothes

The second most important thing to get right is your kit. Get this wrong and your long day out will be a cold and shivery, feet blistered, hot and sweaty, scratch-legged, sore-armed, under-fuelled, miserably long slog. And you will hate each other even more. So choosing what to wear is something you need to spend time giving consideration to.


The Wetsuit

You can use a modified wetsuit but a specific SwimRun wetsuit will pay dividends. Regular wetsuits have just a back zip, but SwimRun wetsuits have a front zip. This means you can constantly regulate your temperature on the run, unzipping it, or taking out your arms and having it hanging at your waist only. On a SwimRun, the swim is usually cold and the run is hot and sweaty, so it is key to be able to slip in and out of your wetsuit, which you will wear for the entire race, easily and quickly.

For anyone who might’ve tried, attempting to put your arms back in a soaking wet wettie is nigh on impossible. Imagine how maddening this will be on race day when you have to do it upwards of 10 times too – not good for that already tested run partner relationship. So, try taking a couple of freezer bags with you, put your hands in the bags, then shoot them though the arms.

The crotch on a SwimRun wetsuit is thinner to enable you to run, and the backside is a different neoprene that is not easily ripped on rocks. The leg seams are sealed so that you can cut the legs where you want. The wetsuit comes with full length legs so you can choose, and the best cut is above the knee to ease running. Wherever you cut, make really, really sure you know where to do it.

Once cut, neither you, nor anyone else, can glue it back on again. Likewise the arms can be cut wherever you prefer, though a lot of people leave these long. Bear in mind you will be wearing a race vest on top of your wetsuit, so the front zip is even more important.

AND… there are pockets inside, genius.



Underneath your wetsuit, you will likely find that shorts and a separate top are better than one piece. It’s unlikely you will be taking your wetsuit off for a call of nature and so this is a matter of personal choice. We will leave you to decide how your own body works under duress on race day!

A pair of jammers is ideal, for both men and ladies, as they won’t ride up and they won’t hold water which you will really appreciate as you leave the water and embark on yet another run. The top needs to have arms which won’t ruckle every time you take your arms in and out of the wetsuit or have excess material that gets caught as you unzip.


Top and toes

Shoes will be worn all the way through the event. You need to run a long way in them, be able to scramble over rocks as you get in and out of the swims, and so you leave them on.

This means you need to choose a pair that will drain quickly. As a tip, you can drill holes in the soles so they don’t hold water. A pair that is fell studded on the soles is ideal. Fell running shoes are designed for running over rough, boggy terrain and so if you have never entered the world of fell running, at least go and check out what they wear on their feet.

With socks there are two options. Short wool-based socks that are ok when wet and a pair of calf guards is one option. Whatever you think of calf guards technically, you need something to keep your legs warm and to get you relatively unscathed through brambles and bracken. The alternative is to wear long socks. These will need to be a pair that will stay up when soaked, so go for long compression socks.

Wear a swim hat under your race cap. Why wouldn’t you if the water is freezing? But remember you need to be able to run in it too.

You will need goggles suitable for open water swimming and always take a spare pair between you that you can both wear. Goggles need to be robust and well-sealed. You will be pulling them on and off, so choose a pair that will not fog up and that have good quality lenses that can cope with varying light conditions.


Time to accessorise

Gloves. This is where it becomes interesting. In a SwimRun you can generally take paddles to assist with extra power in the swim. So you could swim with gloves to keep warm which act a bit like paddles, but think about how you are going to get them on and off when wet.

Alternatively, you could tough it out and swim with paddles glove-free. You put your fingers through some straps at the front, and put a strap at the other end for your wrist. You flip your fingers out of their strapping as you exit the swim and leave the paddle on your wrist. This leaves your hands free as you get on with your run.

Again, what to do with your hands will be a matter of personal choice that you can try out whilst training. If one of you is a stronger swimmer maybe have one of you with and one without paddles to even things up. Make sure to train with paddles if you are going to use them. They put extra pressure on your shoulders so you will need to condition them pre-race.

Pull buoys. Oh yes, don’t forget a pull buoy! Your shod feet will be heavy, so you can take a pull buoy to save your legs, but there is a clever trick. You need to thread some elastic lace through the pull buoy to hold it in place. You attach the pull buoy to your leg, but spin it inside to swim (the elastic means you won’t lose it) and then move it to the outside of your leg to run. There are maximum sizes allowed in some races so check beforehand. Rough up the surface too, and this will stop it from sliding about on your wettie.

Lastly you will probably need a bumbag for some food and mandatory safety items. It needs to be only just big enough and not spin round like a sporran in the water.


The Course

A GPS sports watch is also a good idea. The courses in a SwimRun race are long, and since you are moving over hilly terrain it will help you to keep an eye on the progress you are making. You may not always be able to judge how far you have gone whilst running in a changeable landscape and so it’ll help you with pace setting too. Don’t put your watch on your wrist if your arms are going to be coming on and off in the runs. And make sure you match the units to the units the race is measured in!

On your pull buoy or paddles write down the stage distances, and in a different colour any cut offs and feed stations which will help you pace your race and cut down on any tactical thinking you might need to calculate whilst you are running.

SwimRun is unique, and it’s the kind of endurance race that will appeal to people who enjoy a bit of adventure racing, being in the mountains and don’t mind getting very, very wet. Give it a go, you might find your new calling in life!

Beat Your Fear Of Open Water Swimming

The Open Water season is almost on us and with most would-be triathletes put off by the swim, and for many, this will mark the start of a new challenge, whether that be going longer for an Ironman or simply setting out to conquer a first triathlon.

However, If you’re thinking of trying open water swimming this coming year, here’s how to calm those nerves.

1) Consider location

As you start your open water training, your time in the water will probably be under 30 minutes, which means the last thing you want is an hour commute to a suitable lake.

Choose somewhere nearby that also has changing and shower facilities as well as a safety infrastructure, such as spotters, swim course monitors and even kayak or stand-up paddle board supervision.

2) Get your own wetsuit

It’s tempting to save money and hire a wetsuit, but having your own really makes a difference. For about £100 you can pick up some really great entry-level suits.Pay attention to the sizing charts and make sure it’s a swimming triathlon suit. There is not enough neoprene in a boarding or surf suit so it won’t offer the flexibility you need for an efficient stroke. Hercules can help with this, just give them a call.

3) Practise sighting

There are no lane ropes, lines or walls to help keep you on the right course, therefore you’ll need to pop your head up every now and then to “sight” where you’re heading.You can practise this in the pool before getting in the lake by lifting your head forward every few breaths.

This will strengthen your neck muscles and help you integrate it into your breathing pattern.Spend a few pounds on an anti fog spray for your goggles. Just make sure you wash them in clean water after applying, otherwise the chemical can burn your eyes!

4) Phone a friend

Swimming can be a lonely activity. Some people do it because they like the thinking time and the isolation, but for others being part of a group of like-minded people is motivating. Swimming with a friend or two also improves safety.Usually, there isn’t a shortage of triathletes wanting to swim open water at your local club so join up and team up!

Know Your Sweat

Knowing your ‘Sparkle’ or sweat as some of us know it can be the difference between finishing or not, getting a PB or having issues through the day.

You only have to think back to the infamous race in which Alistair helped Jonathan across the finish line at the World Triathlon Series in Cozumel, Mexico because Jonathan hadn’t got his hydration strategy right.

Every Athlete competitor anticipates, experiments, and maybe stresses a bit (or a lot) about race day nutrition, starting with the foundation of hydration. At our training camps each year we ensure that the athletes understand the importance of the correct level of hydration and we test a couple of times during the camp to ensure that they have nailed it.

They appreciate that dehydration can slow you down, wreak havoc with your gastrointestinal system, and lead to overheating. On the flip side, over hydrating increases your risk for developing exercise associated hyponatremia, a fluid overload condition characterised by abnormally low levels of blood sodium that can be serious and even fatal.

To find your own hydration sweet spot for race day not too much and not too little you can set up a process to check your sweat rate throughout your training season.


You may have heard recently that thirst should drive your drinking. While this is safe and prudent for the recreational exerciser to prevent fluid overload, we can all appreciate that Ironman events are not casual, no matter your race day goals.

Just as you have a planned race day pace, you should also have a paced plan for hydration during the bike and run. However, endurance athletes will need to be prepared to adapt and adjust on race day as well.

Getting started

Start by collecting your own sweat data. You can start anytime, but should do this throughout the training season to capture changes in your sweat rate that occur with increased fitness, acclimatisation, increased training intensity, and of course the full range of potential weather conditions.

Creating a flow sheet for tracking is wise as this allows you to review data from the past as you develop and refine your hydration. Race day weather can differ greatly from recent training conditions due to travel to other climates and venues famous for labile weather conditions.

Looking back at your records allows you to confidently tweak your race nutrition plan accordingly as the race day weather forecast emerges.

How to check your sweat rate

Begin to think of your sweat losses as an hourly rate specific to the bike and to the run. Fuelling guidelines are also described at carbohydrates per hour, so this is a good base for your full race nutrition plan development.

A simple way to monitor hourly fluid losses over a workout is to measure weight changes.

This strategy has been validated against sweat loss measurements in a lab, but there are some ways in which errors can creep into your calculations.

While you are preparing for a long race, it is best to check sweat losses during shorter workouts- about 60 to 90 minutes. That’s because you burn stored fuel or muscle glycogen during exercise, contributing to the weight loss. Longer workouts mean more glycogen and water loss, so it throws off the data.

It is also important to be well hydrated prior to workouts when you are completing a sweat check. Weighing sweaty clothes and hair also throws off your calculations as does consuming solid or semi-solid products during the workout, so stick with liquids.

Here are some guidelines to follow:

Make sure that you are well hydrated for these test sessions.
Weigh in before training but after urinating
Weigh in wearing minimal clothing- only underwear if possible.
After exercising, wear the same minimal clothing used for the weigh in, and weigh in again after towel drying your hair and body.
If you go pee during training, scrap the data collection and try again next time.
Know exactly how much fluid you consume during the training session by measuring the amounts before and after training, or use a graded water bottle.

Important calculations

Every kilogram of weight lost is equal to 1000 ml of sweat.

Fluid consumed during the workout is sweat losses that you did replace, so you add it back in to the weight loss. You can also consume no fluid during these training sessions and skip that step.

Record the following: Weight before and after training; amount of weight lost; triathlon discipline; temperature; humidity; altitude; workout clothing worn; amount of fluid consumed during training; intensity of training; duration of training; date; time of day.

Your standard sweat check procedure is:

Check your weight before and after training, and calculate weight loss.
Convert any weight loss to ml of fluid.
Check/measure the amount of fluid consumed during training.
Add the amount of fluid lost to the amount of fluid consumed to get total fluid losses.
Divide the total amount of fluid lost by the number of hours of training to get fluid losses per hour.

It’s not always possible, or perhaps not even needed to replace all fluid lost during each hour of training and racing.

But knowing your sweat rate does provide a frame of reference for hydrating to minimise your sweat losses and of course sticking with a plan that does not result in fluid overload.

Don’t Leave Your Hydration Strategy to Chance

Most athletes have experienced some of the effects of getting overly dehydrated when out on their long runs/bikes etc. but few really understand the underlying physiological effects on performance as dehydration begins to take its grip.

Managing your hydration is not something that we want to leave to chance, if the aim is to have your best performance. Let’s investigate.

Dehydration and performance: So what happens to your performance when you become dehydrated? It is worth understanding a layman version of the physiological challenge you will place on your body when out training and racing, so that you are able to adopt a plan to avoid some of the effects. I will aim to make it highly approachable, and won’t blind you with scientific jargon.

In basic terms, dehydration is mostly related to your blood. Really? Yes, it is best to think about hydration as it relates to the volume of blood in your body. As an athlete, your blood has three main roles to perform, related to performance:

Deliver oxygen to the muscles to create energy for the work you are doing.
Deliver heat generated from work to the skin, to avoid harmful heat build.
Shift blood to the abdomen, to assist with absorption of any calories consume.

All sound important enough. You have, give or take, about 6 litres of blood in your body. This blood is made up for red blood cells (the red part!), and plasma (the clear fluid, or white part!). As you begin to get dehydrated, a part of the fluid you lose is the white plasma. In other words, there is less blood to go around. In short, as you become more and more dehydrated, there is an ever-increasing competition between the three roles stated above.

In the battle, the winner will always be blood rushing to the skin, as accumulating additional heat within your body is highly corrosive, and even dangerous. This means not only that absorption of calories is compromised, but also that you will begin to experience a higher perception of effort at any work rate, then a greatly increased metabolism cost at that levels. Ultimately, it will become impossible for you to retain your desired pace, as the cost will be too high

Some dehydration is normal: Realise that some dehydration is normal, and one could argue, even a benefit. Most of the negative performance effects of dehydration only occur at about a 4% rate of dehydration. Before that loss, it can be assumed that there is no real performance loss with the minimal dehydration. This is important, as it influences our approach under different conditions.

Imagine you run 60 minutes in a cool environment, it is unlikely that dehydration is going to be a massive performance limiter within that run, assuming you began the run fully hydrated. Now extend the run to multiple hours, and add the environmental cost of heat and humidity. Your first 45 to 75 minutes won’t deliver any negative effects, but your mission will be about setting yourself up for success. While running, it is close to impossible to replenish all fluids you are losing, so the aim should be to prevent yourself from ever getting down to below that level of ‘performance dehydration’.

This takes planning and execution, all of which I lay out below
I should also note that, in addition to simply looking through the performance lens of hydration, you should also look at the fluids you take on as having the role of ‘diluter’ or ‘transporter’.

As mentioned above, your GI system becomes highly inefficient at absorbing calories during exercise, and even less so when becoming dehydrated. The fluids you consume will help offset the potential dehydration, but also should help to dilute the concentration of calories consumed to fuel your exercise.

The more dilute the calories, the easier for an inefficient gut to absorb. No matter your fuel source, it is important that your hydration of choice be a very diluted solution that assists absorption, instead of inhibiting it. A general rule would be for your drink choice to be less than 3% concentration of carbohydrate, with some added electrolytes within the concentration.

If you prefer drinking just water, I would add a dash of salt and a squeeze of citrus, just to get closer to natural body water chemistry, but a sports drink should be highly dilute and not a form of caloric replenishment in itself.

With this information, what is a starting point for approaching hydration for an endurance athlete? Here are my quick tips:

Know the weather: Realise that you require more fluids in hot and humid conditions than cold conditions, as well as the fact that hydration becomes much more important for sessions lasting more than 60 minutes, over short sessions under that duration.

Plan ahead, and begin learning your needs in your weekly training

10-12 ml/kg/hour: A general rule tends to be for about this amount of hydration per hour.

Frequent and often: If you are planning a longer session, begin early and drink frequently and often. I prefer athletes to consume fluids every 6 to 10 minutes, consistently, right from the start of the session.

Dilute those kcal: If you consume any calories, ensure you take on fluids. Similar to above, and realising that for every 100 kcal you consume, it requires about 12 ml of fluid to dilute, quick frequent hits are better than a calorie bomb consumed only when you feel the need.

Re-hydrate between sessions: Even if you nail your training and racing hydration, it is normal to finish in a dehydrated state. To facilitate recovery, limit stress, build a platform of health, and retain balanced energy in the day, ensure you re-hydrate between sessions.

Just because you can, doesn’t make it great: It is very common for me to hear athletes tell me ‘Yes Duncan, but I can go on a 3-hour run and not consume a thing’. This may well be true, but is this approach maximising your performance during the session or the adaptations from that session.

Is it optimal? Being able to ‘survive’ a session with hydration isn’t the same thing as maximising what you hope to achieve from the session.